What were the Navigation Acts and how did they effect the colonies?

The Navigation Acts were a series of laws passed to regulate trade between Great Britain and her colonies, including America. The overall purpose of these laws was to ensure self-sufficiency in the British Empire by reducing reliance on foreign imports. The first Navigation Act of 1651 stipulated that all trade between England the colonies should be carried in English or colonial vessels. This immediately put the British Empire at odds with her main maritime rival, Holland, and soon the two great sea-faring powers were engaged in open conflict, the Anglo-Dutch War of 1652.
On the whole, the Acts proved deeply unpopular with the English colonial settlers in America. The Navigation Act of 1660 stated that a number of valuable products such as sugar, spice, cotton, and tobacco could only be shipped to England or an English province. This measure was a sop to English merchants, who wanted the lion's share of the lucrative trade in these items, none of which could be grown on English soil.
Inevitably, the Act meant that traders in the American colonies lost out, and so it was no surprise that an increasing number of them resorted to smuggling as a means of keeping inter-colonial trade going. For instance, North Carolina kept up a thriving business in bootleg tobacco, which it traded—in direct contravention of the Navigations Acts—with the Massachusetts and Rhode Island colonies.